This disclosure relates to a gas turbine engine, and more particularly to turbine vane cooling arrangements that may be incorporated into a gas turbine engine. More particularly, the disclosure relates to an airfoil and baffle that forms a serpentine cooling passage.
Gas turbine engines typically include a compressor section, a combustor section and a turbine section. During operation, air is pressurized in the compressor section and is mixed with fuel and burned in the combustor section to generate hot combustion gases. The hot combustion gases are communicated through the turbine section, which extracts energy from the hot combustion gases to power the compressor section and other gas turbine engine loads.
Both the compressor and turbine sections may include alternating series of rotating blades and stationary vanes that extend into the core flow path of the gas turbine engine. For example, in the turbine section, turbine blades rotate and extract energy from the hot combustion gases that are communicated along the core flow path of the gas turbine engine. The turbine vanes, which generally do not rotate, guide the airflow and prepare it for the next set of blades.
The vanes typically include a hollow airfoil that is provided a cooling air from a bleed air source to supply cooling fluid to film cooling holes in the airfoil as well as convectively cool the vane. One type of vane has a baffle arranged in a large airfoil cavity. The baffle creates a serpentine passage with the interior surface of the airfoil on both the pressure and suction sides. As the cooling air travels through the serpentine, it convectively cools the part, picking up heat, resulting in the last passage of the serpentine having extremely hot cooling air. The film exiting this last passage is also very hot, resulting in high film temperatures and metal temperatures near the last serpentine passage, which is undesirable.